Magnetic Coils

Magnetic particle testing is done by inducing a magnetic field in a ferro-magnetic material and dusting the surface with iron particles (either dry or suspended in a liquid). Surface imperfections will allow the magnetic field to leak out of the part, distort the magnetic field and concentrate the iron particles near imperfections, thus indicating their presence. Magnetic Particle Inspection or Testing uses magnetic leakage fields to detect surface and subsurface cracks and discontinuities.